I’m not sure how NextScripts works, but it seems that plugin uses a hook that is executed when the post is saved. ACF also use this hook to process the custom field data, but it seems has a conflict with NextScripts. Could you please get in touch with their support to get more information regarding this issue?
Also, please keep in mind that modifying the core file (acf-input.min.js) is not a good thing to do.
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